1. Field of the Invention
The present invention relates to a file transferring system for storing time-series data generated with a lapse of time and for transferring the data at an arbitrary point of time. In particular, the present relates to a file management method and a transfer processing suitable to transfer various kind of data each being in a small quantity.
2. Description of the Related Art
In the file control method of a conventional data processing system, individual data sets to be transferred are controlled on the assumption that each data set exists in a different file disposed for the transfer of the data set. In other words, when a file name is specified, a data set is determined. Consequently, when the same file name is to be used for a plurality of data sets in a transfer operation, the file name is required to be assigned to the new data set in place of the old data set for each transfer operation. In this case, therefore, in addition to a transfer file directly specified at a file transfer, there is required a separate transaction file on the transmission side for temporarily storing data which is generated in the system and which cannot be stored in the transfer file. On the other hand, in addition to a transfer file used to receive transferred information, there is required a separate transaction file on the reception side for sequentially storing data moved thereafter from the transfer file.
However, the prior art transferring methods have the following problems.
When the kinds of data to be transferred are increased and hence the number of the files becomes greater, the control of these files is further complicated, for example, an operation to establish correspondence between the transfer files and the transaction files becomes troublesome. Particularly, in the case where a change of a magnetic tape or a replacement of a disk pack is necessary, the operator's intervention is indispensable and therefore the control of media is quite difficult in the operation. Contrarily, a method to avoid the human intervention in such a case raises a problem that the cost for the apparatuses is increased accordingly.